1. Field of the Invention
The present invention relates generally to resin or adhesive dispensing systems, and more particularly to an air powered resin or adhesive dispensing system wherein the relative amount of a resin or an adhesive and activator material to be dispensed can be readily and easily changed by varying the output of an air drive motor where a desired ratio of resin or adhesive with respect to its associated activator is also being achieved based on an operating relationship of the material pumping equipment and the air drive motor.
2. Brief Description of the Prior Art
Equipment for dispensing high viscosity adhesives has been a challenge for the users of structural adhesives for many years. The available options for accomplishing this task were supplied by standard equipment manufacturers producing machines that were designed to pump a wide range of products. The equipment consisted of slave arm piston pumps, or piston pump hydraulic systems with metering pumps that were belt or electric driven. The disadvantage of the slave arm piston pump for 10:1 products was their inability to reliably supply adhesive and activation at the correct ratios. The machines driven by electric motors produced more consistent mix ratios, but the electric motor, which was typically not explosion proof, could not be used in facilities where flammables were used.
Successively, two part or multi-component dispensing systems specifically for dispensing resins, adhesives, acrylic materials, urethanes, and the like are currently marketed by various manufacturers, such as, for example, EMC2 of Sterling Heights, Mich.; GS Manufacturing of Costa Mesa, Calif.; and Ashby Cross Company, Inc. of Topsfield, Mass. While these two part or multi-component systems can be satisfactory from an operational point of view, several operational disadvantages commonly characteristic of such systems do exist.
For example, most of the known multi-component dispensing systems comprise a drive motor operatively connected to a pair of metering pumps which serve to dispense, for example, an adhesive material and an associated activator. In accordance with a first well-known type of system, however, the metering pumps are usually driven by means of a driving gear mounted upon the drive motor. Consequently, if it is desired to change or alter the relative outputs, amounts, or ratios of the adhesive or activator components being dispensed, due for example to the fact that a different proportion or ratio of the resin or adhesive material with respect to its associated activator is required to be used as a result of the use of different adhesives in connection with different applications, or as a result of the use of particular resins or adhesives under different operating or ambient temperature conditions, the conventional dispensing systems cannot readily accommodate or achieve such alterations or changes without major changes or alterations to the drive motor and metering pump assemblies. In particular, for example, the size of the drive motor driving gear, or the size of the metering pump driven gears enmeshed with the drive motor driving gear, cannot be readily changed or altered because the drive motor and metering pumps are mounted at relatively fixed positions with respect to each other. Accordingly, changing the size of the various driving or driven gears alters the center-to-center distances defined between the driving and driven gears which cannot be physically accommodated within the system.
In accordance with a second known type of system, the metering pumps are operatively driven by the drive motor through means of a suitable chain drive mechanism or system. However, again, in order to alter or change the output drive of the metering pumps, the various sprocket components, chains, idlers, and the like need to be changed which is quite time-consuming and results in a substantially expensive amount of system down-time.
In addition, it is also important that the resin or adhesive metering pump and the activator metering pump be able to be separately or independently operated or driven by means of the drive motor. There are several reasons for this requirement. Firstly, it is important to operate the metering pumps separately or independently in order to properly calibrate or test the pumps so as to ensure, for example, that each pump is dispensing the desired amount of material. Along these lines, it is important to be able to calibrate the metering pumps separately or independently in order not to waste material which would therefore be dispensed by means of the other metering pump not being calibrated or tested.
Secondly, in a similar manner, if one of the metering pumps develops, experiences, or exhibits an operational problem, it is again important from the viewpoint of being able to conserve resources or materials to be able to service or perform required maintenance upon such inoperative metering pump without having to operate or run the operative metering pump. In accordance with the conventional chain-driven drive motor and metering pump systems, however, such separate or independent operation of the metering pumps is not possible because both metering pumps are driven by the drive motor in a serial manner. In other words, the driving arrangement is such that the drive motor is operatively connected to a first one of the metering pumps so as to drive such metering pump, and such first metering pump is then in turn operatively connected to the second metering pump. Consequently, in view of the fact that both of the metering pumps are not directly driven by the drive motor but, to the contrary, the second metering pump is driven by the first metering pump, both metering pumps are not able to be separately or independently driven by the drive motor. If the second metering pump is to be driven or operated, then the first metering pump must also be driven or operated.
In U.S. application Ser. No. 09/466,382 filed Dec. 17, 1999 by Merchant, a resin or adhesive dispensing system is disclosed which comprises a hydraulic drive motor, an adhesive metering pump disposed upon a first side of the drive motor, and an activator metering pump disposed upon a second side of the drive motor. The drive motor and metering pumps comprise sprocket members such that the chain drives respectively interconnecting the drive motor sprocket and the metering pump driven sprockets enable the hydraulic drive motor to independently drive the adhesive and activator metering pumps.
However, there is a desire to provide an improved resin or adhesive dispensing system wherein the speed of the drive motor can be varied by air pressure provided by a localized air regulator, such that the varying speed of the air drive motor allows an adjustable output in a range of high and low settings, adding versatility to operation and reduction of required equipment compared to the resin or adhesive dispensing system achieved by U.S. application Ser. No. 09/466,382.
Accordingly, it is an object of the present invention to provide a new and improved resin or adhesive dispensing system.
A further object of the present invention is to provide a new and improved resin or adhesive dispensing system which effectively overcomes the various operational disadvantages or drawbacks characteristic of the prior art or conventional dispensing systems.
A still further object of the present invention is to provide a new and improved resin or adhesive metering system in which the amount of resin or adhesive dispensed may be adjusted during operation.
A still further object of the present invention is to provide a new and improved resin or adhesive dispensing system wherein the relative amount of a resin or an adhesive to be dispensed, with respect to its associated activator, can be readily and easily changed or altered depending upon the particular resin or adhesive being dispensed, the operating or ambient temperature conditions, or the like, such that a predeterminedly desired ratio of resin or adhesive with respect to its associated activator is achieved.
A still further object of the present invention is to provide a new and improved resin or adhesive dispensing system wherein the adhesive or resin and activator metering pumps are capable of being separately and independently driven by means of the drive motor such that one of the metering pumps can be separately and independently calibrated, serviced, and maintained without operating the other metering pump such that resin, adhesive, or activator materials are not needlessly wasted.
A still further object of the present invention is to provide an improved resin or adhesive dispensing system with reduced maintenance and repair requirements.
To attain the objects described, there is provided a new and improved resin or adhesive dispensing system which comprises a low to high output air-powered motor with adjustable settings, an adhesive metering pump disposed upon a first side of the drive motor, and an activator metering pump disposed upon a second side of the drive motor. This arrangement makes it easy to dispense adhesive or activator material independently while purging the machine with new product or during product changeover.
The drive motor and metering pumps comprise sprocket members such that chain drives respectively interconnecting the drive motor drive sprocket and the metering pump driven sprockets enable the air drive motor to independently drive the adhesive and activator metering pumps. In addition, the drive motor and metering pumps are mounted upon mounting brackets which are mounted upon a support platform of a portable cart so as to be laterally adjustable. In this manner, utilization of the laterally adjustable mounting brackets permit differentially sized sprocket members to be mounted, for example, upon the activator metering pump so as to alter the discharge or output amount of the activator pump relative to the output or discharge of the adhesive metering pump whereby the ratio of the activator with respect to the adhesive is able to be readily achieved.